Based on the information provided in the reference, there is no confirmation that Steam currently supports physical security keys (such as FIDO or U2F devices) for account login. The reference specifically details the Steam Guard Mobile Authenticator as a security feature.
The provided reference states:
The Steam Guard Mobile Authenticator is a feature of the Steam Mobile App that provides an additional level of security to your Steam account. The authenticator generates a code that you need to enter every time that you log on to your Steam account.
Understanding Steam's Current Security Measure (Based on Reference)
The reference highlights the Steam Guard Mobile Authenticator as the method Steam uses to provide an additional layer of security beyond just a password.
- What it is: A feature within the official Steam Mobile App.
- How it works: It generates a time-sensitive code.
- Purpose: You must enter this code when logging into your Steam account, adding an extra step to verify your identity.
This method utilizes a time-based one-time password (TOTP) system, commonly associated with authenticator apps on smartphones.
Security Keys vs. Mobile Authenticators
While both mobile authenticator apps and physical security keys serve as forms of two-factor authentication (2FA), they are different technologies:
| Feature | Mobile Authenticator App (TOTP) | Physical Security Key (FIDO/U2F) |
|---|---|---|
| Mechanism | Generates a time-sensitive code | Cryptographically verifies identity |
| Device | Smartphone with an app | USB, NFC, or Bluetooth hardware device |
| Requires Phone? | Yes (for the app) | No (unless connecting wirelessly) |
| Phishing Resistance | Less resistant (code can potentially be phished) | Highly resistant (login tied to origin) |
The provided reference describes only the mobile authenticator method and does not mention support for the hardware-based security key approach.
